Sliding into N152MP was like meeting an old friend. The bright white Mooney with its bold red, yellow, and blue strips looked like most any other late 1980s Mooney until you looked inside or walked around front. There, the tightly cowled nose gave a clue as to what powered the composite three-blade prop–a Porsche engine.

The airplane showed up in Frederick today as ferry pilot Anthony Eyre of Cross Junction, Virginia, stopped by Landmark Aviation, the local FBO, to get a GPS installed before he took the Porsche-powered Mooney to its new home in Ulm, Germany, near Stuttgart. The Stuttgart name, where Porsche is headquartered, dominated a large Porsche decal on the Mooney’s forward-slanting blue tail. Eyre is flying the airplane for Computaplane in Scotland, delivering it to its new owner in Germany, Uwe Sauter, who happens to be an aircraft mechanic and the owner of a Porsche 911.

The Mooney PFM was familiar to me because shortly after I started working at AOPA in 1988, the association purchased one of the unusual airplanes–only about 45 were built. Several of the editors were checked out in the airplane, including me. It was one of the first high-performance airplanes I’d ever flown. I was soon quite comfortable in the efficient airplane, especially since the engine was so easy to operate. Starting it was car-simple: Turn on the key. No cantankerous mags or balky carburetor or fussy fuel injection system to deal with. A dual electronic ignition system and computers handled the start procedure. Power was managed with a single lever that controlled the prop, mixture, and throttle–the holy grail of engine management that manufacturers attempt to bring to market today; and this was 1988.

The engine was smooth and quiet, but the gearbox necessary to amp the engine rpms down to a rate that could be absorbed the prop added weight–some 200 pounds by some estimates, and complexity. AOPA’s Porsche Mooney suffered numerous cracked and leaky gearboxes. The dual bus electrical system was unheard of in light airplanes in those days. Those of us checking out in the airplane found it a bit intimidating. The large red, guarded “Emergency Crossover” switch was your savior if certain electrical failures occurred; or your nemesis if other failures occurred and you threw the emergency switch tying the two buses together and allowed the failure to take out both systems.

In flight, the Porsche Mooney handled like any other Mooney–aside from the Porsche’s stone-simple engine management. It was quick and efficient. Eyre reports that he sees about 155 knots TAS at 9,000 feet on 9 gph.

So why have you probably never heard of one? Because, like many other products ahead of their time, it wasn’t perfect and the embedded competitive products of the day kept their market acceptance; inertia prevailed. The Porsche airplane was a bit slower and definitely heavier than the Lycoming-powered Mooney 201 of the day. There were a few maintenance issues, like the gearbox. Porsche, who was behind the project in conjunction with Mooney Aircraft, attempted to reassure buyers with guaranteed TBO pricing and other maintenance plans. But in the end, consumers wanted their speed and the Porsche model didn’t quite deliver.

In the end, Porsche bought back most of the airplanes through various programs and re-engined them with Continentals and Lycomings. You may be flying such a modified airplane today and not know that it was once N30MP, the Porsche Mooney that AOPA once owned.

Eyre is hoping to leave Frederick July 15 and make it to Germany within a few days, removing what may well be the last Porsche-powered Mooney from North America.

Certainly one of my most significant memories of my flights in the model was pulling up on a ramp with a few people around. To shut the engine off, you just turned off the key–like a car. At that point, the engine and prop simply thudded to an instant stop rather than winding down the way most conventional airplane engines shut down. The result was frequently curious looks from the crowd wondering what it was that you just broke.

My guess is that with a few tweaks the Porsche engine could have been made to run on high-octane auto fuel. Think what that might be worth today as we scramble to figure out a strategy for moving away from leaded avgas. Back to the future. Fly on N152MP.

The PFM’s single-lever power control was ahead of its time–and still is.

The complex dual electrical system was clever but intimidating.

The Porsche logo on the PFM’s tail

Tony Eyre with Mooney PFM before delivery to Germany

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22 Responses to “Visiting an old Mooney friend and wondering why”

To find out what other Porsche powered Mooneys were around, I went to the FAA registry. Pulled up the page for Manufacturer and Model. Input Mooney and M20L. That shows 30 aircraft. Then changed the filter at the top to show engine type. It shows 21 airframes with Porsche engines, one of which is/was 152MP, so still 19-20 types still in the US!http://registry.faa.gov/aircraftinquiry/Mms_Results.aspx?Mmstxt=5870221&conVal=1&PageNo=1
Cool story, I really enjoyed reading it.

The FAA records don’t accurately reflect the number of planes still with Porsche engines. Many were destroyed in Hurricane Charley and many converted to Continental IO550 engines. The records haven’t been updated.

I believe there were 10, now 9, still with Porsche engines that are still in the USA. Only 3 that I know of are actively flying in USA. There are 5 still flying overseas. A number of Robins and Cessna 172’s with this engine are still flying in Europe.

In checking my log book, I found a few hours logged for a checkout in N142MP in 1990. I remember thinking, as an automotive technician, how the Porshe engine and management system would revolutionize GA. We are still waiting. The power curve of the basically automotive engine neccesitated the need for the complicated, heavy reduction gear box. This was it’s downfall. Slower,heavier, and more expensive than the standard M20L, buyers moved on. Great experiment.

I owned Mooney PFM, N911GT which was the 38th of 42 produced. It was years ahead of its time and a fantastic airplane, quiet, smooth and nearly as fast as my previous plane, a Mooney 201. I had Bosch CIS injection which automatically compensated for altitude and air density which allowed a single power lever. That meant there was no prop or mixture control plus because of fan cooling there were not cowl flaps and the curse of shock cooling was eliminated. Mooney was in financial straits and stopped paying their engine bill. That was the real cause of the end of production.

I will vouch for Mark’s description…”quiet, smooth…”
Mark took me for a ride in N911GT. I have been in many small aircraft, and this was the smoothest and quietest ride I have ever experienced. I was really sad when he told me about the Porsche decision to pull the engines.

You guys can carry on about the Porsche powered Mooney but the simlple fact is the Lycoming engine had better performance and this is what ultimately killed the Porsche powered Mooney! Also at the time the Porsche engine parts were much more expensive than Lycoming. I don’t know many pilots who are going to pay more for less performance.

I have been the proud owner of N152MP, the MooneyPFM Porsche Powered plane, since October 1993 as the second owner. I thinks it’s one of the nicest single engine planes so far. Then came the politics and FAA ceasing its certification. With this one still within its time frames, I was able to keep it in annual and enjoy it once in a while, trying to preserve its time limits. I have made friends with a new owner in Germany and with an extremely confident pilot, Tony Eyer, who has flown the PFM up the Northern route to Germany to its new home. I will miss the MooneyPFM. I now have an Ovation and it is nice, but not as smooth, quiet, responsive or as sharp a looker as the PFM! Porsche Powered Rocks!

My PFM, N152MP was based in Bradford, PA (KBFD) since I purchased her in 1993. Dr. Tom Castillenti, a friend of mine and his neighbor, Dr. Nate Graham, also a friend of mine know the author of this blog, Mr. Tom Haines. He is Dr. Nate Graham’s brother-in-law. I’ve been told tha Tom has visited Bradford, PA a time or two and would have loved to have known that MooneyPFM N152MP of Lucarelli’s was based there and he probably would have mentioned it if he had known. I live around the corner from the previous home of Castillenti and Graham. Dr. Thomas Castillenti is an AME if you need a medical, based in Tampa, FL. Look him up.

I’m a mechanic at a Mooney shop. I really enjoyed working on the Porsche Mooney. Always a challenge, and reading the engine manual was great fun, it really challenged my German skills. There was more and better maintenance information in the German half of the page than the english half.?? There is one more rotting away near San Jose, CA, complete with moss on the paint. I had a chance to work on it a couple of years ago.

The PFM was/is a great airplane to fly. It was back in the ’90’s that Ken Shoup of All American had a PFM and a Mooney Turbo 231 for sale and I had a couple of guys inbounding from Alabama to buy one of them and wanted to fly in both to compare… Shoup had the 231 stored at Stinson on the South side and we were at AA’s office at SAT, so Shoup sent me to fly the PFM over to Stinson with the two other big guys aboard. It was a hot summer day here and about 105 degrees. I had mentioned to Ken that I had zero PFM time and he said to just push the throttle control in to go and even full out (idle) if I wanted to come down quickly. No shock cooling of this engine due to the 911 fan by Porsche. I got a kick out of starting that bird. Way more like a car than a plane! Wow, she sounded bad-ass from within the cockpit, so I gave her a testosterone rev or two and off we went to the active. The PFM did not have much useful load numbers, but why I don’t know. We were a bit over gross and on a hot day, she got off quickly and immediately went to about 1100 fpm minute climb and stayed there until I got 3 to 4,000 feet, my assigned altitude. We flew her a bit and had fun doing so as we were all impressed! After arriving at Stinson and pulling the 231 out of the hanger, we took off with about the same fuel load and only got 5-600 fpm that day even though we were weight legal. It was a hot day and fully understandable, but compared to the non turbo’d PFM’s over gross rate of climb? Sick!
Shoup had gotten several PFM’s to sell and I was selling of his inventory as well as mine in those days, so I was able to garner some experience with the PFM. Porsche was hoping to eventually get a 3-4,000 hour TBO, so they sent one of their engineers around to the planes to do a free top overhaul just to see how things were progressing. None of them really needed a top that I was aware of and I sure bent that mechanic’s ear. His first name was Bill and his last escapes me at the moment, but Bill knew his stuff! He also told me that they hoped to make a higher horsepower version with a turbo and that was exciting to hear. I really loved that engine to spite hearing about an occasional engine failure in the vicinity of certain microwave towers, but they fixed that straight away so I was told.
I love Mooney aircraft, but the problem Mooney suffers and has suffered in its past has been in my opinion poor marketing to spite being the best product out there by far. During the ’80’s, people were coming out of flight schools by the droves and many bought airplanes; usually what they learned in, the Cessna’s. There should have been a PFM parked centrally advertising a free ride to flight school graduates so as to show them what a “real” airplane is and how easy the PFM is to fly. How could the PFM compete when it was priced a bit higher than the flagship 252? Couple that with having to change out prop blades every 1500 hours as well as overhaul the gearbox to the tune of around $5800.00 in ’80’s money, and some thousands for the composite blade replacements, well, they set their own death by trying to advertise and compete with airplanes they were already producing.
The PFM had greatness, just overlooked some. I would personally consider operating a PFM as experimental just to keep that great 911 engine purring under that jet-sexy bonnet of the PFM.
zef

Imported one from Canada and maintained it for some time. I remember the first time that I flew it, had3-4 fuel boost pumps all had to be on for takeoff. Ran a compression and had very low compression, Called Bill, the Porsche rep (I think hos name was Bishop?). He talked to me a while and then said Boyd just adjust the valves,that is all that is needed, I usually come out and do it and charge $200 but I’m busy. I hated the single handle throttle, prop & mixture. There was a mod available to install a standard throttle.
Boyd

Came close to buying a PFM after a couple of flights but the aircraft was lacking speed and and payload. I was told a 270 HP model with turbocharger was coming out next. The mistake was made when they came out with the 217 HP engine first. I understood the bigger engine was already developed and ready to go. I saw the engines and talked to reps at 1987 Oshkosh. Porsche invested 200 million on this project and should have gone full tilt on HP. Nobody wants to fly a slower aircraft than is already available in the product line.
The one thing that I have trouble with is not having enough payload with full fuel. The PFM was anemic. I now fly an early Beech 36 with a 920 lb payload with full fuel. I haven’t yet but just add wing tanks and gain another 198 lbs thru the STC. Add a IO-550 and gain another 100 lbs thru the STC. Certain aircraft should be built for expansion. The Beechcraft 36 was built from the begining to take the heavier loads that have evolved.